Glue for the Heart

Biomaterials The surgical attachment or closure of biological tissues typically requires sutures, staples, or glue. Both sutures and staples can cause additional tissue damage, particularly in damaged or juvenile tissue. Existing adhesives can be washed away under in vivo conditions or may not be strong enough to withstand large forces, such as those found in the cardiovascular system. Lang et al. designed a hydrophobic prepolymer based on poly(glycerol sebacate acrylate) (PGSA), which is composed of biocompatible and biodegradable components, and mixed in a photoinitiator. This adhesive was readily spread over a surface and provided a strong bond, even with wet tissue that had been in contact with blood, upon cross-linking during a few seconds of exposure to ultraviolet light. Tests in rats showed that the adhesive could be used to attach a polymer patch to seal up a left-ventricle wall defect, with similar success rates as a suture control group. A second set of tests looked at the closure of ventricular septal defects within a pig heart. Of the four animals that were tested, two were monitored for 24 hours, while the other two were exposed to accelerated heart rate and blood pressure, and in all cases the adhesive held firm. Sci. Transl. Med. 6 , 218ra6 (2014).